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arXiv · 2006.03396

Classical spin liquid or extended critical range in h-YMnO$_3$?

Sofie Janas·Jakob Lass·Ana-Elena Tutueanu·Morten L. Haubro·Christof Niedermayer·Uwe Stuhr·Guangyong Xu·Dharmalingam Prabhakaran·Pascale P. Deen·Sonja Holm-Dahlin·Kim Lefmann
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Abstract

Inelastic neutron experiments on the classical triangular-lattice geometrically frustrated antiferromagnet h-YMnO$_3$ reveal diffuse, gapless magnetic excitations present both below and far above the ordering temperature, $T_N$. The correlation length of the excitations increases as the temperature approaches zero, bearing strong resemblance to critical scattering. We model the scattering as critical spin-spin correlations in a two-dimensional magnetic ground state, and we speculate that this may provide a general framework to understand features typically attributed to classical spin liquids.

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Sofie Janas, Jakob Lass, Ana-Elena Tutueanu, Morten L. Haubro, Christof Niedermayer, Uwe Stuhr, Guangyong Xu, Dharmalingam Prabhakaran, Pascale P. Deen, Sonja Holm-Dahlin, Kim Lefmann. 2020-06-05. Classical spin liquid or extended critical range in h-YMnO$_3$?. https://doi.org/10.1103/physrevlett.126.107203

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